Technologies for such devices and methods are used in order to determine characteristics of patients' measured blood glucose values. The objective is to give the patient as well as the attending medical staff information which enables the patient to deal with his blood glucose values in an improved and appropriate manner.
For people suffering from diabetes, in particular Diabetes Mellitus, it is especially important for them to keep their blood glucose values constantly at a particular level. A precondition for this is knowledge of their blood glucose value which is therefore measured using a blood glucose measuring device set up for this purpose. Blood glucose measuring devices are known in various embodiments.
The international standard way of measuring blood glucose levels are in terms of a molar concentration, measured in mmol/L (millimoles per liter, or millimolar, abbreviated mM). In some countries, mass concentration is measured in mg/dl (milligrams per deciliter). Since the molecular weight of glucose C6H12O6 is about 180 g/mol, for the measurement of glucose, the difference between the two scales is a factor of about 18, so that 1 mmol/L of glucose is approximately equivalent to 18 mg/dl.
If it is determined, on the basis of the measured values, that the blood glucose value has exceeded the recommended level, medicine is administered, for example by means of insulin injection or the oral administration of Metformin, an oral antidiabeticum. If the blood glucose values fall below the ideal or recommended level, sugar must be orally ingested, for example through food or drink. If the ideal level is exceeded for an extended period of time, there is the danger of serious health complications such as blindness, kidney damage, limbs having to be amputated or neuropathy. If the exceeding of the prescribed blood glucose level is for a short time only but considerable, this can lead to nausea, dizziness, sweating or even conditions of confusion. Thus, it is particularly important for a diabetic to know his blood glucose values at all times so that he is able to implement the appropriate measures to avoid the blood sugar values deviating from the ideal levels.
Blood glucose measuring devices with which the blood glucose values of diabetics can be measured is known. For example, see US 2007/0293790 A1, the disclosure of which is hereby incorporated herein by reference in its entirety. Other exemplary devices include those sold by the Applicant under the registered trade mark, ACCU-CHEK®, including the ACCU-CHEK® Compact Plus system and the ACCU-CHEK® Aviva system.
It is known that blood glucose measurements can be made according to a continuous measurement regime. Such measurements are also known as CGM measurements (Continuous Monitoring blood Glucose Measurement). In this process, the blood glucose values are measured continuously in a continuous time period such that, for example, the progress of the blood glucose value can be collected over an entire day. The analysis of the measured blood glucose values can provide for the determination of several day trends. In this way it is possible to determine blood glucose fluctuations dependent on the time of day. A disadvantage of the continuous blood glucose measurements is firstly, due to the continuous measurements, it can lead to high costs and secondly that it leads to discomfort for the diabetic whereby the latter is caused by the permanent wearing of a subcutaneous sensor. This can lead to infections at the point of entry, intolerance of the plaster or skin irritation which prevents the device being worn permanently or for a long period of time, for example several months. A continuous measurement of the blood glucose values is described, for example, in the document, Gross et al., “Performance Evaluation of the MiniMed Continuous Glucose Monitoring System During Patient Home Use”, Diabetes Technology & Therapeutics, 2 (2000)49.
In connection with the continuous monitoring of blood glucose values, it has been proposed to perform a so-called trend analysis. See, for example, US 2008/0287755 A1, the disclosure of which is hereby incorporated herein by reference in its entirety. Trend analysis can enable the rate of change to be determined on the basis of two or more blood glucose value measurements. The period of continuously monitoring can be between about 5 and about 30 minutes. Measurement periods of less than about 10 minutes or more than about 30 minutes can be provided. Within the measurement period, the CGM measurement is performed once per second or once per minute whereby constant or variable cycle lengths can be provided. The known method proposes that the trend thus determined can be presented on a display as a directional arrow.
Furthermore, discontinuous or structured blood glucose measurements are known which are especially also known as SMBG measurements (Self-Monitoring Blood Glucose measurement) and are characterized by the fact that blood glucose values are determined at particular time intervals by means of individual measurements and/or series of measurements. In this way, it is possible, with the help of such blood glucose measurements, which are also known as structured blood glucose measurements, to measure blood glucose values in close proximity to particular events, for example in relation to meals. Disadvantages of structured blood glucose measurement can arise if events relevant for the blood glucose value of the diabetic occur between the measurement times so that they are undetectable. Procedures have been described whereby an individual blood glucose measurement in the scope of a discontinuous measurement is used to determine the time for a subsequent further individual measurement according to certain parameters. The parameters take into account patient and environmental conditions. See, for example, US 2009/0054753 A1, the disclosure of which is hereby incorporated herein by reference in its entirety.
It has also been proposed to graphically present measurement related information. Examples of such presentations can be found in US 2007/0066873 A1, US 2008/0021666 A1, US 2008/0255438 A1, US 2009/0043525 A1, and U.S. Pat. No. 7,399,277 B2, the disclosures of each of which are hereby incorporated herein by reference in their respective entireties.
It is the object of the invention to provide a device for determining blood glucose characteristics and a method with improved user handling.